Self-propelled cleaning device

ABSTRACT

A self-propelled cleaning device includes a chassis with a protrusion, such that a side brush mechanism is proximate to the external periphery of the contour of the chassis, and an elastic element installed between a driving wheel set and the chassis for providing buffer and shock absorption. An interval is formed between the front edge of the chassis and a dust inlet for guiding dust into a dust collecting case in a chassis containing groove, and the containing groove has a first spacer apart from a control unit and a second spacer separating a carrying space from a negative pressure device. The second spacer has a passage interconnecting the containing groove and the carrying space, and the dust collecting case has separated first and second sides. The first side has a negative pressure outlet, and the negative pressure device has a negative pressure guide channel and a negative pressure inlet corresponding to the hollow passage in the second spacer of the chassis containing groove and a negative pressure outlet of the dust collecting case respectively to allow air to flow through.

FIELD OF THE INVENTION

The present invention relates to a cleaning device, and more particularly to a self-propelled cleaning device capable of moving autonomously to perform a cleaning job.

BACKGROUND OF THE INVENTION

In general, a conventional self-propelled cleaning device performs a cleaning job mainly by its circular external periphery and the cleaning device comprises a rod-shaped sweeper installed at the bottom of a chassis or a vacuum port disposed at the bottom of the chassis and facing towards the floor provided for a sweeping or vacuuming operation. To extend the cleaning range, particularly for edges and corners, some cleansing apparatuses install an additional side brush module on the chassis, such that a side brush of the side brush module will sweep the dust of the sweeper along the moving path of the self-propelled cleaning device or the dust outside the vacuum port that faces towards the floor, and then the dust is swept by the sweeper or sucked into a dust collecting case inside the chassis through the vacuum port. In the meantime, the dust collecting case is often disposed in the chassis and connected to a negative pressure device in series, and the negative pressure device is comprised of a motor and a fan horizontally connected to the motor in series. In addition, a driving wheel set for driving the wheels under the chassis comes with a design that adopts an integral mechanism of a motor and wheels, and is connected to a tension spring between shell covers of the wheels, and the tension spring serves as a buffer when the self-propelled cleaning device is moving on a rough surface, so as to improve the stability of the movements and protect internal components from being damaged by shocks or vibrations.

In view of the aforementioned shortcomings of the conventional self-propelled cleaning device, the inventor of the present invention based on years of experience in the related industry to conduct extensive researches and experiments, and finally designed and developed a novel practical self-propelled cleaning device to overcome the shortcomings of the prior art.

SUMMARY OF THE INVENTION

Although the conventional self-propelled cleaning device installs an additional side brush module to assist the sweeper and the vacuum port for the cleaning function, yet the side brush module is driven by the components including the motor and gears inside the chassis, so that the cleaning range of bristles of the side brush is limited since the area of installing the side brush is limited within the external periphery of the circular contour. Particularly, the cleaning range of the bristles of the side brush is affected by the circular chassis easily when the cleaning job is carried out along edges. When the chassis travels towards the front, left or right according to the traveling path, the cleaning range of the bristles of the side brush hardly goes beyond the diameter of the circular chassis, so that a blind spot is formed between edges of a wall and the cleaning range of the bristles of the side brush, and the motor axle of a conventional negative pressure device includes an additional fan installed horizontally and connected in series with the motor axle, and after the dust collecting case is connected, the total length occupies a large portion of the chassis and thus causing a waste of space, particularly for some mini low-end models, which is not conductive to a thin, light, short, and compact design. In addition, the buffer and shock absorption design of the driving wheel set further requires a shell cover installed on the chassis for covering the wheels, and thus further wasting more space which is also not conductive to the design of the mini low-end models with small space.

Therefore, it is a primary objective of the present invention to provide a self-propelled cleaning device can shift the cleaning range of the side brush towards an external side of the chassis, so that the cleaning effect will not be limited by the contour of the chassis.

Another objective of the present invention is to provide a self-propelled cleaning device capable of simplifying the buffer and shock absorption assembly of the driving wheel set to improve the convenience of the assembling process and saving space.

A further objective of the present invention is to provide a self-propelled cleaning device capable of saving space by planning the chassis space.

Another further objective of the present invention is to provide a self-propelled cleaning device with a dust collecting case capable of collecting dust in a limited chassis space.

Another further objective of the present invention is to provide a self-propelled cleaning device capable of accommodating a dust collecting case under the arrangement of the limited space of a containing groove of a chassis.

Another further objective of the present invention is to provide a self-propelled cleaning device with a negative pressure device for generating a negative pressure within a limited chassis space.

Another further objective of the present invention is to provide a self-propelled cleaning device with a chassis having an airflow guiding effect.

To achieve the aforementioned objectives, the present invention provides a self-propelled cleaning device, comprising: a chassis including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control, and the chassis includes a protrusion protruded outwardly from the external periphery of the contour of the chassis, and the side brush mechanism rotates and sweeps the bristles, and the protrusion makes the installation position of the side brush mechanism closer to the external periphery of the contour of the chassis.

To achieve the aforementioned objectives, the present invention further provides a self-propelled cleaning device, comprising: a chassis including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control, and the driving wheel set being provided for driving the wheel by a motor through a gear set in a housing; an elastic element installed between the housing of the driving wheel set and the internal surface of an upper casing of the chassis, such that the driving wheel set can use a pivot as the center of rotation to provide an elastic driving force to maintain the wheel to be in contact with the ground and provide the buffer and shock absorption effects when a vibration is produced.

To achieve the aforementioned objectives, the present invention further provides a self-propelled cleaning device, comprising: a chassis including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control, wherein an upper casing of the chassis has a containing groove with an opening for accommodating the dust collecting case, and the containing groove has a first spacer apart from the control unit and a second spacer for separating a carrying space from the negative pressure device and apart from the containing groove, and an inclined edge is disposed proximate to the top of the second spacer and has a hollow passage for interconnecting the containing groove and the carrying space, and a lower casing disposed under the containing groove has a hollow hole.

To achieve the aforementioned objectives, the present invention further provides a self-propelled cleaning device, comprising: a chassis including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control, wherein the dust collecting case includes a container, a first side and a second side disposed on both sides of the bottom of the collecting space of the container dust respectively and separated with an appropriate interval apart from each other, and the bottom has a dust inlet, and the first side proximate to the top has an inclined surface, so that the first side has an accommodating space concavely formed thereon, and a negative pressure outlet is formed in the accommodating space.

To achieve the aforementioned objectives, the present invention further provides a self-propelled cleaning device, comprising: a chassis including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control, wherein the chassis includes a containing groove for accommodating the dust collecting case, and the dust collecting case includes a container, a first side and a second side disposed on both sides of the bottom of the collecting space of the container dust respectively and separated with an appropriate interval apart from each other, and the bottom has a dust inlet, and the first side has a negative pressure outlet; wherein the containing groove of the chassis has a first spacer apart from the control unit and a second spacer for separating a carrying space from the negative pressure device and has a hollow passage for interconnecting the containing groove and the carrying space with each other, and the negative pressure device has a negative pressure guide channel with a negative pressure inlet corresponding to the hollow passage on the second spacer of the chassis containing groove and the negative pressure outlet on the dust collecting case to allow air to flow through.

To achieve the aforementioned objectives, the present invention further provides a self-propelled cleaning device, comprising: a chassis including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control, wherein the negative pressure device is comprised of a fan driven by a motor, a shaft cover of the fan rotated and driven by the motor, and an outer frame coaxial with the shaft cover and connected to a bottom edge with an appropriate interval apart, and the space between the shaft cover and the outer frame defines an annular airflow passage, and the outer frame has a plurality of vanes disposed around the outer frame; and the annular airflow passage includes a negative pressure guide channel with a flat interval at the top, and a negative pressure inlet formed at an end of the negative pressure guide channel, and the motor drives the shaft cover to link and rotate the vanes of the outer frame, so as to discharge the air in the annular airflow passage to the outside from the vent. As a result, a negative pressure is formed inside the annular airflow passage, and the negative pressure drives the negative pressure guide channel to suck air from the negative pressure inlet.

To achieve the aforementioned objectives, the present invention further provides a self-propelled cleaning device, comprising: a chassis including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control, wherein the chassis has a concave interval with an airflow guiding effect from the front edge of the chassis to the dust inlet, so that the negative pressure airflow can carry and flow the dust easily.

In an apparatus in accordance with a preferred embodiment of the present invention, the protrusion extended outwardly from the external periphery of the chassis can make the installation position of the side brush mechanism closer to the external periphery of the circular contour of the chassis or the side brush mechanism is installed directly on the protrusion. In the meantime, when the bristles carry out the cleaning operation along wall edges, the cleaning range will not be affected by the circular chassis. The bristles can be in contact with the wall edges to sweep dust from corners and edges easily. The design of the elastic element at the top of the housing of the driving wheel set provides an elastic driving force for maintaining the wheels to be in contact with the floor and also provides the buffer and shock absorption effects. Obviously, the invention can improve the convenience of the installation and save spaces. In addition, the design of the dust collecting case connected with the negative pressure device and the design of the negative pressure dust inlet formed directly on the dust collecting case to skip the sweepers can reduce the space of the chassis significantly, so that the overall design can better fit the thin, light, short, and compact requirements of the mini low-end models.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a preferred embodiment of the present invention;

FIG. 2 is a schematic view of the internal mechanism of a chassis with its upper casing removed in accordance with a preferred embodiment of the present invention;

FIG. 3 is a schematic view of the relation of bristles of a side brush with the external periphery of a circular contour of a chassis in accordance with a preferred embodiment of the present invention;

FIG. 4 is a schematic view of a driving wheel set propped and abutted by an elastic element in accordance with a preferred embodiment of the present invention;

FIG. 5 is a schematic view of the internal space of a chassis in accordance with a preferred embodiment of the present invention;

FIG. 6 is an exploded view of a dust collecting case in accordance with a preferred embodiment of the present invention;

FIG. 7 is a cross-sectional view of a dust collecting case in accordance with a preferred embodiment of the present invention;

FIG. 8 is a schematic view of the bottom of a dust collecting case in accordance with a preferred embodiment of the present invention;

FIG. 9 is a cross-sectional view of a negative pressure device in accordance with a preferred embodiment of the present invention; and

FIG. 10 is a cross-sectional view of a dust collecting case and a negative pressure device which are installed in a chassis in accordance with a preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The technical characteristics, contents, advantages and effects of the present invention will be apparent with the detailed description of a preferred embodiment accompanied with related drawings as follows.

With reference to FIG. 1 for a perspective view of a self-propelled cleaning device in accordance with a preferred embodiment of the present invention, the self-propelled cleaning device comprises a chassis 1 in a shape substantially being a circular contour, and formed by engaging an upper casing 11 and a lower casing 12, and the upper casing 11 has a cover 111 that can be opened and separated from the upper casing 11, and the front end of the lower casing 12 at the bottom of the chassis 1 is a concave interval 121 with a section of an upwardly concave width, so that the front edge of the chassis 1 has an airflow guiding effect, and the negative pressure airflow can carry and flow the dust easily.

In FIG. 2, the chassis 1 includes a side brush mechanism 2 for executing a cleaning function, a driving wheel set 3 for carrying and moving the chassis 1, a dust collecting case 4 for collecting dust, a negative pressure device 5 with a vent 51 for discharging air to provide a negative pressure suction, and a control unit 6 for executing a system control. For simplicity, a schematic view of the electronic components installed on the PC board is provided in the figure.

In FIGS. 2 and 3, the chassis 1 has a protrusion 13 protruded from a right front side (or a left front side) of a circular contour on a side towards the front of a travelling path A and provided for installing the side brush mechanism 2, and the side brush mechanism 2 is driven by a motor 21 and has a plurality of radially arranged bristles 22 provided for a rotational sweeping, and the protrusion 13 makes the installation position of the side brush mechanism 2 closer to the external periphery of the circular contour of the chassis 1, or the side brush mechanism 2 can be installed directly on the protrusion 13. In this design, when the chassis 1 is moving forward along the travelling path A, the outermost tangent B of the cleaning range the bristle 22 of the side brush mechanism 2 is shifted by a spacing D towards the outer tangent C of the diameter of the circular chassis 1, so that when the chassis 1 carries out the cleaning operation along wall edges, the cleaning range of the bristles 22 of the side brush mechanism 2 will not be affected by the circular chassis. The bristles 22 are in full contact with the wall edges, and the invention can sweep and clean corners and wall edges.

In FIGS. 2 and 4, the driving wheel sets 3 are symmetrically and respectively installed on both left and right sides of the bottom of the chassis 1, and each driving wheel set 3 drives a wheel 33 by a motor 31 through a gear set 32, and the motor 31 and the gear set 32 of the driving wheel set 3 are installed in and covered by a housing 34, so that the overall mechanism is disposed in a chamber 14 between the upper casing 11 and the lower casing 12, and the wheels 33 are exposed from the bottom of the lower casing 12. The gear set 32 includes a first gear 322 driven by the motor 31 and installed on a first axle 321 pivotally connected to the lower casing 12, and a third gear 324 installed on a same second axle 323 of the wheel 33, wherein a latch portion 341 is disposed at the top of the housing 3 of the driving wheel set 3, such that an end of an elastic element 35 constituted of a spring can be sheathed on the latch portion 341, and the other end of the elastic element 35 can be abutted against the internal surface of the upper casing 11 of the chassis 1, and the elastic element 35 is disposed between the housing 34 and the internal surface of the upper casing 11 of the chassis 1 for providing an elastic driving force to rotate the housing 34 with respect to a pivot 36 (which is used as the axis of rotation) and abut one side to link the wheel 33 on the second axle 323 to maintain the wheel 33 to be in contact with the floor, and provide the buffer and shock absorption effects when the wheel 33 rolls on a rough road to produce vibrations.

In FIGS. 2 and 5, the upper casing 11 has a movably detachable cover 111 and a containing groove 112 with an opening concavely formed under the cover 111, and the containing groove 112 has a first spacer 114 apart from the control unit 6 and second spacer 116 separating the containing groove 112 and a carrying space 115 apart, and an inclined edge 117 is disposed at a position near the top of the second spacer 116 and has a hollow passage 118 formed thereon and provided for interconnecting the containing groove 112 and the carrying space 115, and a positioning interval 123 is disposed on the lower casing 12 at the bottom of the carrying space 115 and formed by the positioning frame edge 122 with a section of an appropriate height; and the lower casing 12 disposed at the bottom of the containing groove 113 has a hollow hole 124.

In FIG. 6, the dust collecting case 4 includes a case cover 41 and a container 42 with a dust collecting space 421 formed therein, and the container 42 has an opening 422 and a bottom 423 disposed opposite to the opening 422.

In FIGS. 7 and 8, a first side 424 and a second side 425 are disposed on both sides of the bottom 423 in the dust collecting space 421 of the container 42 respectively and separated with an appropriate interval apart from each other. The bottom 423 has a dust inlet 426, and the first side 424 at a position near the top has an inclined surface 427, so that the first side 424 has an accommodating space 43 formed at that position and a negative pressure outlet 428 formed thereon. A negative pressure airflow path is formed between the dust inlet 426 and the negative pressure outlet 428, and a mesh filter 44 is installed between the first side 424 and the second side 425 and vertically disposed proximate to the first side 424 with the negative pressure outlet 428.

The dust inlet 426 is formed by a strip embedding element 45 installed at the dust inlet 426, and a fixing edge 451 is formed at the top end of the embedding element 45 and extended outwardly, and a fastener 452 is provided for fixing the fixing edge 451 to the bottom of the bottom 423 of the container 42, and the bottom of the embedding element 45 has a dust inlet 426 whose front and rear sides become downwardly extended front blocking edges 453 and rear blocking edge 454 respectively, wherein the front blocking edge 453 is an element for passing the negative pressure airflow to vacuum the dust, and its downwardly extending length is relatively shorter and it has a plurality of wedge-shaped airflow channels 455. On the other hand, the downwardly extending length of the rear blocking edge 454 is relatively longer and the rear blocking edge 454 almost touches the floor for blocking the negative pressure airflow. A concave interval 429 is formed at the bottom of the bottom 423 of the container 42 at the front side of the front blocking edge 453, so that the negative pressure airflow can carry and flow the dust through easily.

The dust inlet 426 is disposed at the other end inside the dust collecting space 421 and covered by a light and thin shutter 46, and the shutter 46 is pivotally installed to a vertical pivot pin 47 at the bottom 423 next to the dust inlet 426 and can be floated by the negative pressure airflow, so that the dust inlet 426 and the dust collecting space 421 can be interconnected with each other. When the negative pressure airflow stops, the shutter 46 drops to cover the other outlet end 430 of the dust inlet 426 disposed inside the dust collecting space 421. The position of the outlet end 430 is higher than the bottom 423 of the dust collecting space 421, so that the dust entered into the dust collecting space 421 will not fall out from the dust inlet 426.

In FIGS. 2 and 9, the negative pressure device 5 includes a fan 53 driven by a motor 52, a shaft cover 531 driven by the motor 52 for rotating the fan 53, and an outer frame 533 coaxially with the shaft cover 531 and connected to the bottom edge 532 with an appropriate interval apart from each other, and an annular airflow passage 534 is formed in a space between the shaft cover 531 and the outer frame 533, and the outer frame 533 includes a plurality of vanes 535 disposed around the outer frame 533, and the motor 52 is installed in a load compartment 542 of a bottom shell 54 with an opening 541 facing downward, and the bottom shell 54 includes a receiving space 544 disposed around the periphery of the load compartment 542 and being an opening 543 facing upward, and the receiving space 544 is provided for receiving the outer frame 533 and the vanes 535. A negative pressure guide channel 536 being a flat area is disposed at the top of the annular airflow passage 534, and an end of the negative pressure guide channel 536 has a negative pressure inlet 537. The motor 52 drives the shaft cover 531 to link and rotate the vane 535 of the outer frame 533 in order to discharge air in the annular airflow passage 534 to the outside from the vent 51 as shown in FIG. 2, so that a negative pressure is formed inside the annular airflow passage 534, and the negative pressure drives the negative pressure guide channel 536 to suck air from the negative pressure inlet 537.

In FIG. 10, when the dust collecting case 4 and the negative pressure device 5 are installed into the containing groove 112 and the carrying space 115 of the chassis 1 respectively, the negative pressure inlet 537 at the front end of the negative pressure guide channel 536 of the negative pressure device 5 is embedded into a concave space 119 of the second spacer 116 formed on a side of carrying space 115, and the portion of the second spacer 116 protruded from a side of the containing groove 112 is embedded into the accommodating space 43 concavely formed on the first side 424 of the dust collecting case 4, and the negative pressure inlet 537 of the negative pressure device 5 is aligned with the hollow passage 118 on the inclined edge 117 of the second spacer 116 and the negative pressure outlet 428 on the inclined surface 427 of the dust collecting case 4 to allow air to flow through. The negative pressure device 5 is installed precisely in the positioning interval 123 formed by the positioning frame edge 122 of the lower casing 12 at the bottom of the carrying space 115, and concave interval 121 concavely formed at the front end of the bottom of the chassis 1 is extended to the dust inlet 426, so that the front edge of the chassis 1 has an airflow guiding effect, and the negative pressure airflow can carry and flow the dust through the dust inlet 426 and guide the dust into the dust collecting case 4.

In the design of a preferred embodiment of the present invention, the design of the protrusion extended outwardly from the external periphery of the chassis 1 can make the installation of the side brush mechanism 2 closer to the external periphery of the circular contour of the chassis 1 or the side brush mechanism 2 can be installed directly on the protrusion 13. These designs can keep the bristles 22 in full contact with the wall edges, so that when the cleaning operation is carried out along wall edges or corner, the cleaning range will not be affected by the circular chassis and dust at corners or edges can be cleaned. The design of the elastic element 35 at the top of the housing 34 of the driving wheel set 3 not only provides an elastic driving force to maintain the wheels 33 to be in contact with the floor, but also provides the buffer and shock absorption effects. The invention improves the convenience of the installation and save spaces. In addition, the design of the dust collecting case 4 connected to the negative pressure device 5 and the design of waiving the sweeper by forming the negative pressure dust inlet 426 on the dust collecting case 4 directly can reduce the space of the chassis 1 significantly, so that the overall design better fits the thin, light, short, and compact requirements of the mini low-end models.

While the invention is described in some detail hereinbelow with reference to certain illustrated embodiments, it is to be understood that there is no intent to limit it to those embodiments. On the contrary, the aim is to cover all modifications, alternatives and equivalents falling within the spirit and scope of the invention as defined by the appended claims.

In summation of the above description, the present invention herein enhances the performance than the conventional structure and further complies with the patent application requirements and is submitted to the Patent and Trademark Office for review and granting of the commensurate patent rights. 

What is claimed is:
 1. A self-propelled cleaning device, comprising: a chassis, including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control; wherein, the chassis has a protrusion protruded and extended from the external periphery of the contour of the chassis, and the side brush mechanism performs a rotational sweeping by a driven bristle, and the protrusion moves the installation position of the side brush mechanism closer to the external periphery of the contour of the chassis.
 2. The self-propelled cleaning device of claim 1, wherein the bristle of the side brush mechanism has a cleaning range with an outermost tangent deviated by a spacing from the outermost tangent of the diameter of the chassis.
 3. A self-propelled cleaning device, comprising: a chassis, including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control; wherein, the driving wheel set uses a motor to drive a wheel by a gear set installed in a housing; and an elastic element is installed between the housing of the driving wheel set and a surface of an inner side of the upper casing of the chassis, and the driving wheel set uses a pivot as the center of rotation, and the elastic element provides an elastic driving force to maintain the contact of the wheel with the ground and provides buffer and shock absorbing effects when a vibration is produced.
 4. A self-propelled cleaning device, comprising: a chassis, including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control; wherein, an upper casing of the chassis has an inwardly and concavely formed containing groove with an opening for accommodating the dust collecting case, and the containing groove has a first spacer apart from the control unit and a second spacer for separating the containing groove from a carrying space of the negative pressure device, and an inclined edge is formed at a position near the top of the second spacer and has a hollow passage for interconnecting the containing groove and the carrying space with each other, and the lower casing disposed at the bottom of the containing groove has a hollow hole.
 5. The self-propelled cleaning device of claim 4, wherein the dust collecting case includes a container, and a first side and a second side formed on both sides of the bottom of the container dust collecting space respectively and separated with an appropriate interval apart from each other, and the bottom has a dust inlet, and an inclined surface is disposed at a position near the top of the first side, such that an accommodating space is concavely formed on the first side and disposed at the position, and the accommodating space has a negative pressure outlet formed thereon.
 6. The self-propelled cleaning device of claim 4, wherein the negative pressure device includes a fan driven by a motor, a shaft cover driven by the motor to rotate the fan, and an outer frame coaxial with the shaft cover and connected to the bottom edge with an appropriate interval apart from each other, and an annular airflow passage is formed in a space between the shaft cover and the outer frame, and the outer frame has a plurality of vanes formed around the outer frame, and a negative pressure guide channel with a flat area is formed at the top of the annular airflow passage, and an end of the negative pressure guide channel has a negative pressure inlet, and the motor drives the shaft cover to link and rotate the vanes of the outer frame in order to discharge the air inside the annular airflow passage to the outside through the vent, so that a negative pressure is formed inside the annular airflow passage, and the negative pressure drives the negative pressure guide channel to suck air from the negative pressure inlet.
 7. A self-propelled cleaning device, comprising: a chassis, including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control; wherein the dust collecting case includes a container, a first side and a second side disposed on both sides of the bottom inside the container dust collecting space respectively and separated with an appropriate interval apart from each other, and the bottom has a dust inlet, and an inclined surface is disposed at a position near the top of the first side, so that an accommodating space is concavely formed on the first side and at the position, and the accommodating space has a negative pressure outlet.
 8. A self-propelled cleaning device, comprising: a chassis, including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control; wherein, the chassis has a containing groove for accommodating the dust collecting case, and the dust collecting case includes a container, and a first side and a second side disposed on both sides of the bottom inside the bottom of the container dust collecting space and separated with an appropriate interval apart from each other, and the bottom has a dust inlet, and the first side has a negative pressure outlet, and the containing groove of the chassis has a first spacer apart from the control unit and a second spacer apart from a carrying space of the negative pressure device, and the second spacer has a hollow passage for interconnecting the containing groove and the carrying space with each other, and the negative pressure device has a negative pressure guide channel with a negative pressure inlet aligned with the hollow passage on the second spacer of the chassis containing groove and the negative pressure outlet of the dust collecting case to allow air to flow through.
 9. The self-propelled cleaning device of claim 8, wherein the first side of the dust collecting case has an accommodating space concavely formed therein, and the second spacer of the chassis has a concave space formed on a side of the carrying space and a portion protruded from a side of the containing groove, and the negative pressure inlet of the negative pressure device is embedded into the concave space, and the portion protruded from the containing groove of the second spacer is embedded into the accommodating space concavely formed on the first side of the dust collecting case.
 10. The self-propelled cleaning device of claim 5, 7 or 8, further comprising a negative airflow path formed between the dust inlet and the negative pressure outlet and situated between the first side and the second side, and a mesh filter vertically installed and disposed proximate to the first side of the negative pressure outlet.
 11. The self-propelled cleaning device of claim 5, 7 or 8, wherein the dust inlet is comprised of a strip embedding element installed at the dust inlet, and a fixing edge is formed and extended from the top end of the embedding element, and a fastener is provided for fixing the fixing edge to the bottom of the container.
 12. The self-propelled cleaning device of claim 5, 7 or 8, wherein the dust inlet has a front blocking edge and a rear blocking edge extended downward from the front and rear sides of the dust inlet respectively, and the front blocking edge is a component for passing a negative pressure airflow for vacuuming dust, and the front blocking edge has a relatively shorter downwardly extended length and includes a plurality of wedge-shaped airflow channels, and the rear blocking edge has a relatively longer downwardly extended length and almost reaches the floor for blocking the negative pressure airflow from passing through.
 13. The self-propelled cleaning device of claim 5, 7 or 8, wherein the dust inlet is disposed at an outlet end inside the dust collecting space and covered by a shutter, and the shutter is pivotally installed to a vertical pivot pin on the bottom adjacent to the dust inlet.
 14. The self-propelled cleaning device of claim 5, 7 or 8, wherein the dust inlet is disposed at an outlet end inside the dust collecting space and situated at a position higher than the bottom of the dust collecting space.
 15. A self-propelled cleaning device, comprising: a chassis, including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for collecting dust, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control; wherein, the negative pressure device includes a fan driven by a motor, a shaft cover driven by the motor to rotate the fan, and an outer frame coaxial with the shaft cover and connected to the bottom edge with an appropriate interval apart from each other, and an annular airflow passage is formed between the shaft cover and the outer frame, and the outer frame has a plurality of vanes formed around the outer frame, and a negative pressure guide channel with a flat area is formed at the top of the annular airflow passage, and an end of the negative pressure guide channel has a negative pressure inlet, and the motor drives the shaft cover to link and rotate the vanes of the outer frame in order to discharge the air inside the annular airflow passage to the outside through the vent, so that a negative pressure is formed inside the annular airflow passage, and the negative pressure drives the negative pressure guide channel to such air from the negative pressure inlet.
 16. The self-propelled cleaning device of claim 6 or 15, wherein the motor is installed in and covered by a load compartment of a bottom shell with an opening facing downward, and the bottom shell has a receiving space disposed around the periphery of the load compartment and being an opening facing upward, and the receiving space is provided for receiving the outer frame and the vanes.
 17. A self-propelled cleaning device, comprising: a chassis, including a side brush mechanism for executing a cleaning function, a driving wheel set for carrying and moving the chassis, a dust collecting case for guiding and collecting dust from a dust inlet, a negative pressure device having a vent for discharging air to provide a negative pressure suction, and a control unit for executing a system control; wherein, a concave interval with an airflow guiding effect is extended from the front end of the bottom of the chassis to the dust inlet, so that the negative pressure airflow can carry and flow dust easily.
 18. The self-propelled cleaning device of claim 4 or 8, wherein the negative pressure device is installed in a positioning interval formed precisely at a positioning frame of the lower casing under the carrying space. 